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ATA5771C/73C/74C
UHF ASK/FSK Transmitter with the Atmel AVR Microcontroller
DATASHEET
General Features
● Atmel® AVR® microcontroller and RF transmitter PLL in a single QFN24 5mm × 5mm package (pitch 0.65mm) ● Operating frequency ranges 310MHz to 350MHz, 429MHz to 439MHz and 868MHz to 928MHz
● Temperature range –40°C to +85°C ● Supply voltage 2.0V to 3.6V allowing usage of single Li-cell power supply ● Low power consumption
● Active mode: typical 9.8mA at 3.0V and 4MHz microcontroller-clock ● Power-down mode: Typical 200nA at 3.0V ● Modulation scheme ASK/FSK ● Integrated PLL loop filter ● Output power of 8dBm at 315MHz / 7.5dBm at 433.92MHz / 5.5dBm at 868.3MHz ● Easy to design-in due to excellent isolation of the PLL from the PA and power supply ● Single-ended antenna output with high efficient power amplifier ● Very robust ESD protection: HBM 2500V, MM100V, CDM 1000V ● High performance, low power AVR 8-bit microcontroller ● Advanced RISC architecture ● Non-volatile program and data memories ● 4Kbytes of in-system programmable program memory flash ● 256Bytes in-system programmable EEPROM ● 256Bytes internal SRAM ● Programming lock for self-programming flash program and EEPROM data security ● Peripheral features ● Two timer/counter, 8- and 16-bit counters with two PWM channels on both ● 10-bit ADC ● On-chip analog comparator ● Programmable watchdog timer with separate on-chip oscillator ● Universal serial interface (USI)
9137J-RKE-10/14
● Special microcontroller features ● debugWIRE on-chip debug system ● In-system programmable via SPI port ● External and internal interrupt sources ● Pin change interrupt on 12 pins ● Enhanced power-on reset circuit ● Programmable brown-out detection circuit ● Internal calibrated oscillator ● On-chip temperature sensor
● 12 programmable I/O lines
2 ATA5771C/73C/74C [DATASHEET]
9137J–RKE–10/14
1. General Description
The Atmel® ATA5771C/73C/74C is a highly flexible programmable transmitter containing the Atmel AVR® microcontroller Atmel ATtiny44V and the UHF PLL transmitters in a small QFN24 5mm × 5mm package. This device is a member of a transmitter family covering several operating frequency ranges, which has been specifically developed for the demands of RF low-cost data transmission systems with data rates up to 32kBit/s using ASK or FSK modulation. Its primary applications are in the application of Remote Keyless-Entry (RKE), Passive Entry Go (PEG) System and Remote Start. The ATA5771 is designed for 868MHz application, whereas ATA5773 for 315MHZ application and ATA5774 for 434MHz application.
Figure 1-1. ASK System Block Diagram
UHF ASK/FSK Remote Control Transmitter
S1 PXY S1 PXY S1 PXY
PXY PXY PXY PXY
Atmel ATA577x
VDD GND PXY PXY PXY PXY PXY
VS
Power up/down
ENABLE
GND_RF f/4 PLL CLK
UHF ASK/FSK Remote Control Receiver
Demod
Control
1 to 6 Microcontroller
XTO
VCO
PA
VCC_RF
VS
PA_ENABLE ANT2
ANT1
Antenna
Loop Antenna
VS
LNA
PLL XTO VCO
ATA5771C/73C/74C [DATASHEET]
9137J–RKE–10/14
3
Figure 1-2. FSK System Block Diagram
UHF ASK/FSK Remote Control Transmitter
S1 PXY S1 PXY S1 PXY
PXY PXY PXY PXY
Atmel ATA577x
VDD GND PXY PXY PXY PXY PXY
VS
Power up/down
ENABLE
GND_RF f/4 PLL CLK
UHF ASK/FSK Remote Control Receiver
Demod
Control
1 to 6 Microcontroller
XTO
VCO
PA
VCC_RF
VS
PA_ENABLE ANT2
ANT1
Antenna
Loop Antenna
LNA
PLL XTO VCO
VS
4 ATA5771C/73C/74C [DATASHEET]
9137J–RKE–10/14
2. Pin Configuration
Figure 2-1. Pinning QFN24 5mm × 5mm
GND ENABLE GND_RF VS_RF XTAL GND
VCC PB0 PB1 PB3/RESET PB2 PA7
24 23 22 21 20 19 1 18
2 17
3 16
4 15
5 14
6 13 7 8 9 10 11 12
PA0 PA1 PA2 PA3/T0 PA4/USCK PA5/MISO
PA6/MOSI CLK
PA_ENABLE ANT2 ANT1 GND
Table 2-1.
Pin 1 2 3 4 5 6 7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Pin Description
Symbol VCC PB0 PB1
PB3/RESET PB2 PA7
PA6 / MOSI
CLK
PA_ENABLE ANT2 ANT1 GND
PA5/MISO PA4/SCK PA3/T0
PA2 PA1 PA0 GND XTAL VS_RF GND_RF ENABLE GND GND
Function Microcontroller supply voltage Port B is a 4-bit bi-directional I/O port with internal pull-up resistor Port B is a 4-bit bi-directional I/O port with internal pull-up resistor Port B is a 4-bit bi-directional I/O port with internal pull-up resistor/reset input Port B is a 4-bit bi-directional I/O port with internal pull-up resistor Port A is an 8-bit bi-directional I/O port with internal pull-up resistor Port A is an 8-bit bi-directional I/O port with internal pull-up resistor Clock output signal for microcontroller. The clock output frequency is set by the crystal to fXTAL/4 Switches on power amplifier. Used for ASK modulation Emitter of antenna output stage Open collector antenna output Ground Port A is an 8-bit bi-directional I/O port with internal pull-up resistor Port A is an 8-bit bi-directional I/O port with internal pull-up resistor Port A is an 8-bit bi-directional I/O port with internal pull-up resistor Port A is an 8-bit bi-directional I/O port with internal pull-up resistor Port A is an 8-bit bi-directional I/O port with internal.